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    <title>Document</title>
    <style>
        .hide {
            display: none;
        }

        .box:hover p {
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        .box:hover ul {
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<body>

    <div class="box">
        军事
        <ul class="hide">
            <li>111</li>
            <li>222</li>
            <li>333</li>
        </ul>
        <p class="hide">11111111111</p>
    </div>

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